Donald Lopez, in the introduction to his Elaborations on Emptiness, describes explanation as a “leveling”, Etymologically this description is accurate, although I’ve never thought of “explanation” in those terms. To explain a text or statement is to make plain its meaning. To explain a state of affairs is to make plain the causal mechanism that gives rise to a it. The “plain” in “explain” means to make obvious or visible. The “plain” in ex-plain is not plain as in ordinary or homely, neither remarkable for beauty or ugliness, but “plain” as in undecorated, free of superficial ornament. Both plain and explain derive from the same Latin root. The Latin explanare, according to M-W, derives from planus, level or flat. Across a level or flat or unobstructed space it is possible to plainly see what is on the other side.